Heated or refrigerated dispensers for delivering liquid or semi-liquid food products are commonly used in foodservice restaurants, catering, convenience stores and other commercial or public food establishments. The known dispensers are usually adapted for receiving food bags in a housing and for delivering the food by using pumps and/or gravity forces to a dispensing area.
Food products, such as cheese sauces, usually requires to be served at warm temperature to adapt to culinary habits and/or to improve the digestion of fat. Other food products are adapted to be stored and dispensed cold such as salsa, ketchup or condiment sauces. Other foods are adapted to be dispensed at refrigerated temperatures such as UHT cream, yogurt, acidified milk based food or pudding. These food products may be easily subjected to bacterial spoilage when opened, whereby heating or cooling permits to keep the food in safer bacteriological conditions. The products usually need to be stored in aseptically hermetic flexible packages such as pouches, which are opened at the time the product is dispensed and therefore become sensitive to airborne pathogens. The pouches are usually of relatively large size, in general of several kilograms, thus requiring a relatively long time before obtaining a controlled hot/cool temperature acceptable for serving.
A fully warm/cool food package may not be rapidly available when the demand for food exceeds the warming/cooling operation time for the new package. There is also a risk of bacterial contamination or spoilage when the package is opened before the product reaches a sufficiently safe temperature level, i.e., about 60° C. in the case of hot product or below 4–6° C. for refrigerated products.
For instance, the American NSF standards require that potential hazardous food products having a pH level of 4.6 or less to be rethermalized, i.e., heated from refrigerated or ambient state to an elevated temperature of not less than 140° F., within four hours. For example, by using existing commercial equipment, the average heat-up time for large size pouches is of more than 3 hours, most often more than 5 hours and sometimes more than 10 hours, before the temperature in the center part of the pouch can be raised from ambient to an acceptably warm temperature of 60° C. In order to meet with these regulations, prior solutions consisted in pre-warming the bag in a hot water bath or in microwave oven, then transferring the preheated bag to the dispensing unit where the bag remains temperature controlled.
Similarly, there are food products that are preferably served slightly below ambient, such as cold sauce, salsa, ketchup, condiments and the like, so that the shelf life of the product in the dispensing unit can be prolonged significantly. Especially in hot seasons and non air-conditioned rooms, it is advisable to keep these type products at a temperature below 18° C., and preferably below 15° C. or lower.
U.S. Pat. No. 5,803,317 relates to a heated dispensing apparatus for dispensing products at elevated temperature which allows packaging of the product in a container, such as a flexible bag, with a discharge tube extending therefrom. The dispenser includes a receptacle with an outlet opening in the lower portion thereof and a pump adjacent to the outlet opening. A heater is provided for heating the food bag in a large heat-conductive receptacle and the discharge tube passing through the pump and maintaining both the bag and the tube at a desired elevated temperature. The receptacle is permanently mounted on the dispenser frame and accommodates the reception of a bulky flexible package with a fitment protruding on one side of the package.
Several known dispensers include U.S. Pat. No. 6,003,733, which relates to an apparatus for the dispensing of heated viscous food product using convection means, and U.S. Pat. No. 6,016,935, which relates to a viscous food dispensing and heating/cooling assembly which is adapted to receive large food reservoirs of the “bag-in-box” type. U.S. Pat. Nos. 6,056,157 and 6,223,944 relate to a dispensing device for a flowable substance comprising a housing comprising walls to define a compartment, a heating unit for maintaining the compartment at a predetermined temperature, a valve for selectively controlling flow of the material from the package.
U.S. Pat. No. 6,488,179 relates to a disposable aseptic cassette dispenser with a control center for controlled dispensing and heating of flowable and semi-flowable materials. A comprising a plurality of non-flexible aseptic cassettes are mounted on a base of the dispenser. A dispensing means is also provided for dispensing flowable or semi-flowable material. Each of the cassette contains one or more heating elements.
German company Herman Roelofsen GmbH manufactures food dispensing units comprising a relatively wide box-shaped aluminum container adapted to receive a flexible food bag. The bag is loosely housed within the container and a bar inserted in two slots of the container hangs up the bag to avoid collapsing of the bag within the container. The container fits within a heating metal compartment of the unit which is heated by flexible heating devices. Due to heat loss in the transitions and air gaps from the heaters to the food, the dispensing unit has poor heating performance on large size bags with an heat-up time of more than 10 hours from ambient state for cheese sauce bags. Microwave preheating of the bag is required before the bag can be installed in the dispensing unit.
Thus, there is a need in the art for improved dispensing systems, which are easy to load and use, and which preferably occupy minimal lateral footprint space.